Mercury Retrograde

 

DEDICATION

To my wonderful husband, who always hears me. I love you.

 

CONTENTS

 

N
o matter how decent Petra Dee's intentions were, things always went to shit.

Sweat dribbled down the back of her neck, sliding down her shoulder blades and congealing between her skin and the Tyvek biohazard suit. The legs of the suit made a
zip-­zip
sound, snagging on bits of prickly pear as she walked through the underbrush of Yellowstone National Park. She clutched her tool bag tightly in her gloved grip, the plastic of the suit rustling over the hiss of the respirator in her ears. Her breath fogged the scuffed clear mask of the suit, softening the edges of the land before her with a dreamlike filter.

“You don't have to do this,” Mike said.

“Consider it a professional favor, okay?” she said. “And you said it was weird. Now, I'm curious.”

The park ranger in the suit in front of her stopped, turned, and awkwardly grabbed her sleeve. “Look, you don't have to. The hikers who found it said it was pretty gruesome.” Mike's voice was muffled behind his own mask, but his brow creased as he looked at her. It was clear to her that he now thought better of bringing her here. Maybe it was his dumb, misplaced sense of chivalry, or maybe things really did suck as badly as he suggested. With him, it was hard to tell.

“You can go back,” he suggested. Again.

“Mike. You need a geologist. There isn't anybody on your staff who can tell you if it's safe to be up here. Weird seismic shit has been happening in the last ­couple of weeks—­new springs and fumaroles and mudpots opening up in this area, stuff that isn't on the maps. And you're stuck with me unless you want to wait for the Department of the Interior to show up and tell you what you need to know.” She didn't want to be having this discussion out in the open. There were more men and women in suits behind them, far behind, waiting to see what Mike and Petra would do. They might not be within earshot, but it offended her sense of professionalism. “Besides, I owe you.”

And she did, big-­time. Petra had a knack for causing trouble for Mike. Since she'd shown up in town two months ago to take a quiet-­sounding geology gig with the federal government, she'd managed to stumble into an underground war between a cattle baron and the local drug-­dealing alchemist. A shitstorm of administrative paperwork had been generated for Mike when drugs and bodies turned up in his jurisdiction. Pizza and beer only went so far to balance the scales of debt.

Mike rubbed the back of his hood with a crinkling sound. “Yeah, but . . .”

Petra nodded sharply. “I can do this.” Her voice sounded steadier than she felt.

“If you need outta here, just say the word.” Mike started walking again, pushing aside a branch blocking her way.

She moved forward to the edge of the tree line, beyond where blotches of color swam in her sweaty vision. A campsite. A red tent had been pitched in a clearing, though it tilted in a lopsided fashion on a broken pole, like a giant spider someone had plucked a leg from. Nice tent—­a deluxe model, with mesh windows and pop-­outs. A dead fire with cold ash was surrounded by a ring of rocks. Laundry dangled from a clothesline: T-­shirts, jeans, socks.

And beyond it, a gorgeously pink mudpot. Iron in the underlying slurry likely yielded the soft rose color. The acidic hot spring burbled mud, steaming into the cool air. She was reminded of the steam rising from mountains as the dew baked off in the spring. There were thousands of these mudpots dotted all throughout Yellowstone National Park, too many to catalog, despite the hazards they posed.

Petra ducked under the clothesline, wrestling for a moment with a pair of child-­sized purple leggings that seemed determined to get snagged around her respirator hose. After fighting them off, she turned her attention back to the scene.

A dark-­haired man sat upright at the edge of the dead fire, hunched forward, his arms tangled in a blanket as if he'd been trying to protect himself from the cold.

Her breath echoed quickly in her mask. Mike moved forward to kneel before the man. Pulling the blanket off, he reached for his neck to take his pulse.

Early morning sunshine illuminated the man's face. It was slack, jaw open, violet tongue protruding from his lips. Broken capillaries covered his cheeks, the red contrasting with mottled grey skin. His eyes were frozen wide open, and the sclera were bright red instead of white.

The blanket fell away to reveal a red flannel shirt. Oddly enough, it looked as if part of it had been bleached, as if he'd brushed up against a gallon of white paint. A knife glinted in his right hand, trapped in a claw frozen by rigor mortis. Petra squinted to get a good look. The knife was a piece of junk—­the blade had been melted.

The body rolled over on its side, landing like an action figure holding its pose in the dirt.

Mike swore and grabbed his radio. “This is L-­6, be advised that we've confirmed a male victim. Tell the medics to . . .”

Petra turned. That was a big tent. Too big for just one guy. And then there were the little girls' leggings that she'd tussled with . . . damn it. Steeling herself, she crossed to the tent, her suit creaking. Sweating, she grasped the tent zipper. Its teeth stuck in the PVC-­coated canvas, and she tried three times before she gave up. Part of the tent had come unstaked on the right side, letting daylight creep in. She worked that seam and pulled it open.

She stumbled back, falling on her ass.

A woman sat bolt upright in a sleeping bag, with speckled and broken skin like the man at the fireside. She stared at Petra with the same blood-­red gaze under a tangle of brown hair.

Petra leaned forward to touch her shoulder. The woman didn't move, frozen in some unfathomable moment of shock. Heart hammering, Petra fumbled for a pulse. Through her gloves, the woman felt cold, and her chest didn't move. Her skin felt swollen, as if stretched over an unseen trauma.

Mike crawled into the tent to stare at a bundle beside the woman. He peeled back a sleeping bag on a little girl, maybe five or six, clutching a dinosaur plush toy. Her eyes were closed, seeming very peaceful under bruised skin.

“Please let her be alive,” Petra whispered.

Mike shook his head. “No pulse. But . . . not a mark on her.”

Petra backed out of the tent into the clearing. Blinking, she reached for her equipment bag and dug out a handheld yellow gas monitor. Stabbing at the buttons, she waited for the sensors to start analyzing the air.

She glanced at the mudpot, that beautiful pink jewel barely the size of a bathtub. The warmth it radiated condensed against her plastic suit. When the call came in that a man had been found dead near a mudpot in Yellowstone, the rangers had all assumed that the culprit was poisonous gas, carbon dioxide or hydrogen sulfide. And that would make sense, but . . .

While waiting for the gas monitor to calibrate, Petra stood to peer into the bubbling mud. It was possible, but poisoning by those gases was a relatively rare phenomenon. She fished some tongue depressors out of her pack to dip a glob of the mud out into a specimen bottle for analysis.

A sharp drumming sounded overhead, and she looked up.

A woodpecker drilled into a pine tree above her, making a sound like a jackhammer. Birds had much more delicate respiratory systems than humans. If poisonous gas had seeped up from the mud here, then the bird should be showing ill effects. But instead it had found its breakfast, plucking bugs from bark, ignoring the humans below.

Her gaze scraped the perimeter of the camp. The vegetation was all wrong here—­brittle and yellow and spotted, as if burned by something acidic. She knelt to pluck a piece of curled grass to stuff into a specimen bottle. Low-­level amounts of hydrogen sulfide were likely to enhance plant growth. High levels could kill plants, but not quickly.

She glanced down at her gas detector. “Huh.”

Mike had backed away from the tent. “Well?”

“No carbon monoxide. No sulfur dioxide. Normal amounts of carbon dioxide. No appreciable levels of hydrogen sulfide right now, which is what I assumed the culprit would be, since that's the most common airborne poison spewed by mudpots.” She pulled the hood of her suit back to take a sniff of the air. It smelled like pine needles, not like rotten eggs. “I think that it's safe for your ­people to come in. Just . . . tell them not to touch anything they don't have to. Gloves and suits.”

Mike nodded and began barking orders into his walkie-­talkie.

Petra lifted her freckled face to the sky, feeling the blessedly cool breeze against her cheeks. She spat a bit of dark blond hair out of her mouth and reached to take another soil sample. Maybe there was some other toxin here? Something more exotic that would need more tests run. Arsenic could be here, but it wouldn't have killed these ­people so quickly. The ground was opening up in pockets in the whole Pelican Creek area. Geologists had been detecting midlevel quakes in previously quiet land. In a place like Yellowstone, the geology was always changing, but this was unusual. And it needed to be investigated.

Mike mopped his brow. “Maybe there were high levels here overnight, and the wind swept it all away,” he mused. “Or the mudpot belched. A one-­time thing.”

“Could be.” Inspiration struck her, and she stood to examine the man's body by the dead fire. He lay where he'd fallen, rigidly on his side. “Could you help me with him?”

“Sure. What do you need?”

“I need to check his pockets for change.”

Mike rolled the guy over. The body didn't turn over with a normal thick, human sound. Petra heard sloshing, as if they were moving a cooler full of melted ice. Mike came up with a set of car keys and a fistful of change, which he handed to Petra. She stared at the debris, pushing aside the quarters, nickels, and dimes in her palm.

“Whatcha lookin' for?”

“Pennies . . . ah.” She held a penny up to the light. A 2015 penny, bright and shiny and new. “It wasn't hydrogen sulfide poisoning.”

“How can you tell?”

“If he'd been exposed to hydrogen sulfide, the copper in the penny would have oxidized. No evidence of that, here. When hydrogen sulfide was used as a chemical weapon in World War I, copper coins in the pockets of victims turned nearly black.”

“Great. Maybe the coroner's toxicology report will tell us what it was. I'm mostly just concerned that we've got an ongoing hazard situation here.”

“I'll run some soil samples,” Petra said. “In the meantime, you should have your rangers cordon this off for at least a hundred yards until we know for sure what it was.” She wrinkled her nose and reached for her respirator. “What the hell is that smell?” It wasn't the rotten-­eggs smell of hydrogen sulfide. This smelled worse, like roadkill.

Mike turned to the body. “It . . .” The smell hit him, and he struggled to pull his hood over his head. “It's the body.”

Where the camper's corpse had been turned over to the earth, a black, viscous substance oozed. Two medics had arrived in full gear and grasped the body, one at the arms and the other at the feet. As they lifted, it seemed as if some fragile surface tension held by the man's skin failed. The skin split open, and dark fluid soaked the dirt to splash against the white suits of the medics.

“Christ,” Mike said behind his mask. “Only a floater would behave like that.”

“A floater?” she echoed.

“A body that's been in a river for weeks. The gases build up while the organs rot. But . . . these guys can't have been here that long. We'll know for sure when we get an ID.”

More plastic suits showed up with body bags into which to pour what remained of the camper. They discussed how best to remove the woman and the child from the tent without rupturing them. It was decided to start with the child.

Petra turned away. She just didn't want to see that. She began picking at samples around the edge of the campsite, trying to fade into the background. But the scene burned behind her eyelids. It wasn't just the ­people that were dead. Death had spread to the vegetation around the campsite in a circle, as if someone had sprayed the plants with weed killer. As she ventured farther and farther away, she found a trail of rust-­colored grass vanishing into the forest.

Ignoring the chatter and radio static behind her, she began to follow the trail. It spanned an area a little over three feet wide, a perfect path of brittle vegetation that contrasted sharply with the early autumn grass that still thrived. She paused before a pine tree that seemed to have had its bark scorched away by some kind of chemical reaction.

She began to regret removing her hood. Holding her breath, she chipped a piece of bark away with an awl and dropped it into a sample bottle.

The track ended abruptly at a spine of rocks that composed the next ridge. There were no plants to speak of here, only fine milk quartz pebbles and sandstone gravel.

She blew out her breath, frustrated at having lost the trail. Had there been some kind of chemical accident here? She ran through the desiccants and herbicides she knew, most of which were not good for ­people, but the most likely short-­term effects would have been simple respiratory distress or skin contact allergies. Nothing that could cause the amount of squish and slop that the medics were dealing with.

No rational explanation.

Maybe there was an irrational one.

She glanced behind her. No one had followed her this far, to the edge of the forest. She fumbled in her gear bag for the last bit of equipment she'd brought: a golden compass. Glinting in the sun, it lay flat in the palm of her hand. Seven rays extended to the rim, with an image of a golden lion devouring the sun in the center. The Venificus Locus, a magic detector that she still wasn't entirely sure she believed in, but couldn't discount. Maybe it would have something to say. Maybe it wouldn't. But not asking the question would be stupid.